Now, that shocking scene caught on camera at a busy subway station near boston. A mother and her son, falling on the subway track during the chaos of rush hour. It's a scene almost too shocking to watch. A woman, holding her young son, rushing across this crowded train platform. And then, straight over the edge. Watch again. From the back of the crowd, 36-year-old mirra sackrar, on the tracks with her son. He falls from her arms, handing perilously close to the high-voltage third rail. I -- it was on that platform. Reporter: Horrified by bystanders in this boston train station wednesday, leaping into action, after the pair makes that four-foot drop. A woman jumping down and lifts the mother up, as a man scoops up her son. A rescue that took only ten seconds. It was just like that. Reporter: Incredibly, neither tsracra nor her son suffered any injuries. It was really stupid of me. Again, the station was packed. She was distracted, in a hurry. We've obviously all been there. But thankfully, all of those people were there to help her and her son. I'm always moved when people act so quickly and unselfishly. Instincts. Josh, thank you. Now, to the elite code of confidentiality about to be

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